ESTUDYR
ALS/ACLS - RED CROSS FINAL EXAM 2025 MULTICHOICE
ANSWERED EXAM QUESTIONS WITH DETAILED
RATIONALES
1. The resuscitation team suspects that hyperkalemia is the cause of cardiac arrest. Which ECG finding
would support this diagnosis?
A. ST-segment elevation in all leads
B. Bradycardia with narrow QRS
✅C. Wide-complex ventricular rhythm or tall, pointed T waves
D. Presence of delta waves
Rationale:
Hyperkalemia affects cardiac conduction by delaying depolarization, leading to tall, peaked T waves, and
eventually wide QRS complexes or sine wave patterns. These are hallmark ECG signs of hyperkalemia.
2. A patient with dyspnea and altered mental status is brought to the ED. The ECG shows sinus
bradycardia. Which agent should the team administer?
A. Epinephrine 1 mg IV push
✅B. Atropine 0.5 mg every 4 to 5 minutes
C. Amiodarone 300 mg IV bolus
D. Adenosine 6 mg IV rapid push
Rationale:
Atropine is the first-line treatment for symptomatic bradycardia. It blocks parasympathetic influences,
increasing the heart rate. It is given at 0.5 mg IV every 3–5 minutes, up to 3 mg total.
3. A patient with an unstable bradyarrhythmia does not respond to atropine or transcutaneous
pacing. What is the next appropriate intervention?
A. Synchronized cardioversion
✅B. Administration of an epinephrine infusion
C. Intravenous diltiazem
D. Defibrillation at 200 joules
Rationale:
If atropine and pacing fail in unstable bradyarrhythmias, epinephrine infusion is used to stimulate beta-1
receptors, increasing heart rate and cardiac output.
,ESTUDYR
4. A stable patient has a heart rate of 130 bpm. Which patient statements would the team identify as
possible contributing factors to this tachyarrhythmia? (Select all that apply)
✅A. "I've had a terrible cold with a horrible cough and fever the past week."
✅B. "I've been so anxious lately because I just lost my job."
✅C. "I've been vomiting for the past 2 days from a gastrointestinal bug."
D. "I had coffee this morning but no other symptoms."
Rationale:
Fever, anxiety, and dehydration from vomiting can all cause sinus tachycardia. They are common, non-
cardiac causes of a stable narrow-complex tachyarrhythmia.
5. A patient with narrow-complex supraventricular tachycardia (SVT) and stable vital signs should first
receive which intervention?
A. Adenosine 6 mg IV rapid push
✅B. Vagal maneuvers
C. Atropine 0.5 mg IV
D. Amiodarone 150 mg over 10 minutes
Rationale:
Vagal maneuvers are the first-line treatment for stable SVT. They activate the parasympathetic nervous
system to slow AV nodal conduction and may terminate the arrhythmia.
6. A stable patient with ventricular tachycardia and a corrected QT interval of 0.50 seconds requires
which intervention?
✅A. Synchronized cardioversion
B. Defibrillation
C. Adenosine
D. Atropine
Rationale:
Synchronized cardioversion is indicated in stable patients with monomorphic VT and a pulse, especially
with a prolonged QTc, which increases the risk of Torsades de Pointes.
7. Which ECG finding is most characteristic of atrial fibrillation?
, ESTUDYR
A. Regular rhythm with narrow QRS
✅B. Absence of P waves with irregularly irregular QRS complexes
C. Sawtooth flutter waves
D. Wide QRS complexes with fusion beats
Rationale:
Atrial fibrillation is identified by the absence of discrete P waves and a hallmark “irregularly irregular”
ventricular response due to chaotic atrial activity.
8. A pulseless patient presents with the ECG showing wide QRS complexes and a regular rhythm.
What is the rhythm likely to be?
✅A. Ventricular tachycardia
B. Atrial flutter
C. Asystole
D. First-degree AV block
Rationale:
Pulseless VT is a shockable cardiac arrest rhythm characterized by a wide-complex tachycardia without a
pulse. Immediate defibrillation is indicated.
9. A patient with acute renal failure has peaked T waves before experiencing cardiac arrest. What is
the likely underlying cause?
A. Hypocalcemia
✅B. Hyperkalemia
C. Hypoglycemia
D. Hypernatremia
Rationale:
Hyperkalemia is common in renal failure and causes ECG changes such as tall T waves and wide QRS
complexes, potentially leading to cardiac arrest.
10. A patient with ventricular tachycardia is found to have abnormal serum electrolytes. Which
imbalances are most likely contributing to this arrhythmia? (Select all that apply)
✅A. Hypomagnesemia
✅B. Hypocalcemia
C. Hypernatremia
D. Hyperglycemia
ALS/ACLS - RED CROSS FINAL EXAM 2025 MULTICHOICE
ANSWERED EXAM QUESTIONS WITH DETAILED
RATIONALES
1. The resuscitation team suspects that hyperkalemia is the cause of cardiac arrest. Which ECG finding
would support this diagnosis?
A. ST-segment elevation in all leads
B. Bradycardia with narrow QRS
✅C. Wide-complex ventricular rhythm or tall, pointed T waves
D. Presence of delta waves
Rationale:
Hyperkalemia affects cardiac conduction by delaying depolarization, leading to tall, peaked T waves, and
eventually wide QRS complexes or sine wave patterns. These are hallmark ECG signs of hyperkalemia.
2. A patient with dyspnea and altered mental status is brought to the ED. The ECG shows sinus
bradycardia. Which agent should the team administer?
A. Epinephrine 1 mg IV push
✅B. Atropine 0.5 mg every 4 to 5 minutes
C. Amiodarone 300 mg IV bolus
D. Adenosine 6 mg IV rapid push
Rationale:
Atropine is the first-line treatment for symptomatic bradycardia. It blocks parasympathetic influences,
increasing the heart rate. It is given at 0.5 mg IV every 3–5 minutes, up to 3 mg total.
3. A patient with an unstable bradyarrhythmia does not respond to atropine or transcutaneous
pacing. What is the next appropriate intervention?
A. Synchronized cardioversion
✅B. Administration of an epinephrine infusion
C. Intravenous diltiazem
D. Defibrillation at 200 joules
Rationale:
If atropine and pacing fail in unstable bradyarrhythmias, epinephrine infusion is used to stimulate beta-1
receptors, increasing heart rate and cardiac output.
,ESTUDYR
4. A stable patient has a heart rate of 130 bpm. Which patient statements would the team identify as
possible contributing factors to this tachyarrhythmia? (Select all that apply)
✅A. "I've had a terrible cold with a horrible cough and fever the past week."
✅B. "I've been so anxious lately because I just lost my job."
✅C. "I've been vomiting for the past 2 days from a gastrointestinal bug."
D. "I had coffee this morning but no other symptoms."
Rationale:
Fever, anxiety, and dehydration from vomiting can all cause sinus tachycardia. They are common, non-
cardiac causes of a stable narrow-complex tachyarrhythmia.
5. A patient with narrow-complex supraventricular tachycardia (SVT) and stable vital signs should first
receive which intervention?
A. Adenosine 6 mg IV rapid push
✅B. Vagal maneuvers
C. Atropine 0.5 mg IV
D. Amiodarone 150 mg over 10 minutes
Rationale:
Vagal maneuvers are the first-line treatment for stable SVT. They activate the parasympathetic nervous
system to slow AV nodal conduction and may terminate the arrhythmia.
6. A stable patient with ventricular tachycardia and a corrected QT interval of 0.50 seconds requires
which intervention?
✅A. Synchronized cardioversion
B. Defibrillation
C. Adenosine
D. Atropine
Rationale:
Synchronized cardioversion is indicated in stable patients with monomorphic VT and a pulse, especially
with a prolonged QTc, which increases the risk of Torsades de Pointes.
7. Which ECG finding is most characteristic of atrial fibrillation?
, ESTUDYR
A. Regular rhythm with narrow QRS
✅B. Absence of P waves with irregularly irregular QRS complexes
C. Sawtooth flutter waves
D. Wide QRS complexes with fusion beats
Rationale:
Atrial fibrillation is identified by the absence of discrete P waves and a hallmark “irregularly irregular”
ventricular response due to chaotic atrial activity.
8. A pulseless patient presents with the ECG showing wide QRS complexes and a regular rhythm.
What is the rhythm likely to be?
✅A. Ventricular tachycardia
B. Atrial flutter
C. Asystole
D. First-degree AV block
Rationale:
Pulseless VT is a shockable cardiac arrest rhythm characterized by a wide-complex tachycardia without a
pulse. Immediate defibrillation is indicated.
9. A patient with acute renal failure has peaked T waves before experiencing cardiac arrest. What is
the likely underlying cause?
A. Hypocalcemia
✅B. Hyperkalemia
C. Hypoglycemia
D. Hypernatremia
Rationale:
Hyperkalemia is common in renal failure and causes ECG changes such as tall T waves and wide QRS
complexes, potentially leading to cardiac arrest.
10. A patient with ventricular tachycardia is found to have abnormal serum electrolytes. Which
imbalances are most likely contributing to this arrhythmia? (Select all that apply)
✅A. Hypomagnesemia
✅B. Hypocalcemia
C. Hypernatremia
D. Hyperglycemia
